論文 - 冨田　勝

Metabolomic study of Chilean biomining bacteria Acidithiobacillus ferrooxidans strain Wenelen and Acidithiobacillus thiooxidans strain Licanantay

Martínez P., Gálvez S., Ohtsuka N., Budinich M., Cortés M.P., Serpell C., Nakahigashi K., Hirayama A., Tomita M., Soga T., Martínez S., Maass A., Parada P.

Metabolomics （Metabolomics）  9 （ 1 ） 247 - 257 2013年02月

ISSN  15733882

　概要を見る

In this study, we present the first metabolic profiles for two bioleaching bacteria using capillary electrophoresis coupled with mass spectrometry. The bacteria, Acidithiobacillus ferrooxidans strain Wenelen (DSM 16786) and Acidithiobacillus thiooxidans strain Licanantay (DSM 17318), were sampled at different growth phases and on different substrates: the former was grown with iron and sulfur, and the latter with sulfur and chalcopyrite. Metabolic profiles were scored from planktonic and sessile states. Spermidine was detected in intra- and extracellular samples for both strains, suggesting it has an important role in biofilm formation in the presence of solid substrate. The canonical pathway for spermidine synthesis seems absent as its upstream precursor, putrescine, was not present in samples. Glutathione, a catalytic activator of elemental sulfur, was identified as one of the most abundant metabolites in the intracellular space in A. thiooxidans strain Licanantay, confirming its participation in the sulfur oxidation pathway. Amino acid profiles varied according to the growth conditions and bioleaching species. Glutamic and aspartic acid were highly abundant in intra- and extracellular extracts. Both are constituents of the extracellular matrix, and have a probable role in cell detoxification. This novel metabolomic information validates previous knowledge from in silico metabolic reconstructions based on genomic sequences, and reveals important biomining functions such as biofilm formation, energy management and stress responses. © 2012 The Author(s).

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Identification of a replication initiation protein of the pVV8 plasmid from Thermus thermophilus HB8

Ohtani N., Tomita M., Itaya M.

Extremophiles （Extremophiles）  17 （ 1 ） 15 - 28 2013年

共著, 査読有り,  ISSN  14310651

　概要を見る

Recently, the extremely thermophilic bacterium Thermus thermophilus HB8 has been demonstrated to harbor a circular plasmid designated by pVV8 in addition to two well-known plasmids, pTT8 and pTT27, and its entire sequence has been determined. The absence of any obvious replication initiation gene in the 81. 2 kb plasmid prompted us to isolate its minimum replicon. By in vivo replication assays with fragments deleted in a stepwise manner, a minimum replicon containing a single ORF, TTHV001, was identified. A protein encoded by TTHV001 showed no amino acid sequence similarity to other function-known proteins. As the results of in vivo and in vitro experiments strongly suggested that the TTHV001 protein was involved in the replication initiation of pVV8, the protein and the gene were referred to as RepV and repV, respectively. The RepV protein binds to an inverted repeat sequence within its own repV gene and then triggers the unwinding of the DNA duplex in an A + T-rich region located just downstream from the inverted repeat. The in vivo replication assays with minimum replicon mutants in the RepV binding site or the unwinding region demonstrated that the unwinding in the region by the RepV binding was essential for pVV8 replication initiation. © 2012 Springer Japan.

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Metabolic and morphological changes of an oil accumulating trebouxiophycean alga in nitrogen-deficient conditions

Ito T., Tanaka M., Shinkawa H., Nakada T., Ano Y., Kurano N., Soga T., Tomita M.

Metabolomics （Metabolomics）  9 （ (Suppl 1) ） 178-187 - 187 2013年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  15733882

　概要を見る

Oil-rich algae have promising potential for a next-generation biofuel feedstock. Pseudochoricystis ellipsoidea MBIC 11204, a novel unicellular green algal strain, accumulates a large amount of oil (lipids) in nitrogen-deficient (-N) conditions. Although the oil bodies are easily visualized by lipophilic staining in the cells, little is known about how oil bodies are metabolically synthesized. Clarifying the metabolic profiles in -N conditions is important to understand the physiological mechanisms of lipid accumulations and will be useful to optimize culture conditions efficiently produce industrial oil. Metabolome and lipidome profiles were obtained, respectively, using capillary electrophoresis- and liquid chromatography-mass spectrometry from P. ellipsoidea in both nitrogen-rich (+N; rapid growth) and -N conditions. Relative quantities of more than 300 metabolites were systematically compared between these two conditions. Amino acids in nitrogen assimilation and N-transporting metabolisms were decreased to 1/20 the amount, or less, in -N conditions. In lipid metabolism, the quantities of neutral lipids increased greatly in -N conditions; however, quantities of nearly all the other lipids either decreased or only changed slightly. The morphological changes in +N and -N conditions were also provided by microscopy, and we discuss their relationship to the metabolic changes. This is the first approach to understand the novel algal strain's metabolism using a combination of wide-scale metabolome analysis and morphological analysis. © 2012 The Author(s).

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Metabolomic profiling of lung and prostate tumor tissues by capillary electrophoresis time-of-flight mass spectrometry

Kami K., Fujimori T., Sato H., Sato M., Yamamoto H., Ohashi Y., Sugiyama N., Ishihama Y., Onozuka H., Ochiai A., Esumi H., Soga T., Tomita M.

Metabolomics （Metabolomics）  9 （ 2 ） 444-453 - 453 2013年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  15733882

　概要を見る

Metabolic microenvironment of tumor cells is influenced by oncogenic signaling and tissue-specific metabolic demands, blood supply, and enzyme expression. To elucidate tumor-specific metabolism, we compared the metabolomics of normal and tumor tissues surgically resected pairwise from nine lung and seven prostate cancer patients, using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). Phosphorylation levels of enzymes involved in central carbon metabolism were also quantified. Metabolomic profiles of lung and prostate tissues comprised 114 and 86 metabolites, respectively, and the profiles not only well distinguished tumor from normal tissues, but also squamous cell carcinoma from the other tumor types in lung cancer and poorly differentiated tumors from moderately differentiated tumors in prostate cancer. Concentrations of most amino acids, especially branched-chain amino acids, were significantly higher in tumor tissues, independent of organ type, but of essential amino acids were particularly higher in poorly differentiated than moderately differentiated prostate cancers. Organ-dependent differences were prominent at the levels of glycolytic and tricarboxylic acid cycle intermediates and associated energy status. Significantly high lactate concentrations and elevated activating phosphorylation levels of phosphofructokinase and pyruvate kinase in lung tumors confirmed hyperactive glycolysis. We highlighted the potential of CE-TOFMS-based metabolomics combined with phosphorylated enzyme analysis for understanding tissue-specific tumor microenvironments, which may lead to the development of more effective and specific anticancer therapeutics. © 2012 The Author(s).

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Physiological and environmental parameters associated with mass spectrometry-based salivary metabolomic profiles

Sugimoto M., Saruta J., Matsuki C., To M., Onuma H., Kaneko M., Soga T., Tomita M., Tsukinoki K.

Metabolomics 9 （ 2 ） 454-463 - 463 2013年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  15733882

　概要を見る

Mass spectrometry (MS)-based metabolomic methods enable simultaneous profiling of hundreds of salivary metabolites, and may be useful to diagnose a wide range of diseases using saliva. However, few studies have evaluated the effects of physiological or environmental factors on salivary metabolomic profiles. Therefore, we used capillary electrophoresis-MS to analyze saliva metabolite profiles in 155 subjects with reasonable oral hygiene, and examined the effects of physiological and environmental factors on the metabolite profiles. Overall, 257 metabolites were identified and quantified. The global profiles and individual metabolites were evaluated by principle component analysis and univariate tests, respectively. Collection method, collection time, sex, body mass index, and smoking affected the global metabolite profiles. However, age also might contribute to the bias in sex and collection time. The profiles were relatively unaffected by other parameters, such as alcohol consumption and smoking, tooth brushing, or the use of medications or nutritional supplements. Temporomandibular joint disorders had relatively greater effects on salivary metabolites than other dental abnormalities (e. g., stomatitis, tooth alignment, and dental caries). These findings provide further insight into the diversity and stability of salivary metabolomic profiles, as well as the generalizability of disease-specific biomarkers. © 2012 Springer Science+Business Media New York.

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Computational analysis of associations between alternative splicing and histone modifications

Shindo Y., Nozaki T., Saito R., Tomita M.

FEBS Letters （FEBS Letters）  587 （ 5 ） 516-21 - 521 2013年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  00145793

　概要を見る

Pre-mRNA splicing is a complex process involving combinatorial effects of cis- and trans-elements. Here, we focused on histone modifications as typical trans-regulatory elements and performed systematic analyses of associations between splicing patterns and histone modifications by using publicly available ChIP-Seq, mRNA-Seq, and exon-array data obtained in two human cell lines. We found that several types of histone modifications including H3K36me3 were associated with the inclusion or exclusion of alternative exons. Furthermore, we observed that the levels of H3K36me3 and H3K79me1 in the cell lines were well correlated with the differences in alternative splicing patterns between the cell lines. © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

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Physical Laws Shape Biology

Selvarajoo, K. and Tomita, M.

Science Feb 8 339   646 2013年

研究論文（学術雑誌）, 単著, 査読有り

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Comprehensive computational analysis of bacterial CRP/FNR super family and its target motifs reveals stepwise evolution of transcriptional networks

Matsui M., Tomita M., Kanai A.

Genome Biology and Evolution （Genome Biology and Evolution）  5 （ 2 ） 267-282 - 282 2013年

研究論文（学術雑誌）, 共著

　概要を見る

The cAMP receptor protein (CRP)/fumarate and nitrate reduction regulatory protein (FNR)-type transcription factors (TFs) are members of a well-characterized global TF family in bacteria and have two conserved domains: the N-terminal ligand-binding domain for small molecules (e.g., cAMP, NO, or O2) and the C-terminal DNA-binding domain. Although the CRP/FNR-type TFs recognize very similar consensus DNA target sequences, they can regulate different sets of genes in response to environmental signals. To clarify the evolution of the CRP/FNR-type TFs throughout the bacterial kingdom, we undertook a comprehensive computational analysis of a large number of annotated CRP/FNR-type TFs and the corresponding bacterial genomes. Based on theamino acid sequence similarities among 1,455 annotated CRP/FNR-type TFs, spectral clustering classified the TFs into 12 representative groups, and step wise clustering allowed us to propose a possible process of protein evolution. Although each cluster mainly consists of functionally distinct members (e.g., CRP, NTC, FNR-like protein, and Fix K), FNR-related TFs are found in several groups and are distributed in a wide range of bacterial phyla in the sequence similarity network. This result suggests that the CRP/FNR-type TFs originated from an ancestral FNR protein, involved in nitrogen fixation. Furthermore, a phylogenetic profiling analysis showed that combinations of TFs and their target genes have fluctuated dynamically during bacterial evolution. A genome-wide analysis of TF-binding sites also suggested that the diversity of the transcriptional regulatory system was derived by the stepwise adaptation of TF-binding sites to the evolution of TFs. © 2013 The Author(s).

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Quantitative assay for TALEN activity at endogenous genomic loci

Hisano Y., Ota S., Arakawa K., Muraki M., Kono N., Oshita K., Sakuma T., Tomita M., Yamamoto T., Okada Y., Kawahara A.

Biology Open （Biology Open）  2 （ 4 ） 363-367 - 367 2013年

研究論文（学術雑誌）, 共著, 査読有り

　概要を見る

Artificially designed nucleases such as zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs) can induce a targeted DNA double-strand break at the specific target genomic locus, leading to the frameshiftmediated gene disruption. However, the assays for their activity on the endogenous genomic loci remain limited. Herein, we describe a versatile modified lacZ assay to detect frameshifts in the nuclease target site. Short fragments of the genome DNA at the target or putative off-target loci were amplified from the genomic DNA of TALEN-treated or control embryos, and were inserted into the lacZa sequence for the conventional blue-white selection. The frequency of the frameshifts in the fragment can be estimated from the numbers of blue and white colonies. Insertions and/or deletions were easily determined by sequencing the plasmid DNAs recovered from the positive colonies. Our technique should offer broad application to the artificial nucleases for genome editing in various types of model organisms.

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Contribution of quantitative changes in individual ionic current systems to the embryonic development of ventricular myocytes: A simulation study

Okubo, C., Sano, H., Naito, Y. and Tomita, M.

Journal of Physiological Sciences （Journal of Physiological Sciences）  63 （ 5 ） 355-67 - 367 2013年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  18806546

　概要を見る

Early embryonic rodent ventricular cells exhibit spontaneous action potential (AP), which disappears in later developmental stages. Here, we used 3 mathematical models - the Kyoto, Ten Tusscher-Panfilov, and Luo-Rudy models - to present an overview of the functional landscape of developmental changes in embryonic ventricular cells. We switched the relative current densities of 9 ionic components in the Kyoto model, and 160 of 512 representative combinations were predicted to result in regular spontaneous APs, in which the quantitative changes in Na+ current (I Na) and funny current (I f) made large contributions to a wide range of basic cycle lengths. In all three models, the increase in inward rectifier current (I K1) before the disappearance of I f was predicted to result in abnormally high intracellular Ca2+ concentrations. Thus, we demonstrated that the developmental changes in APs were well represented, as I Na increased before the disappearance of I f, followed by a 10-fold increase in I K1. © 2013 The Author(s).

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Capillary electrophoresis-mass spectrometry-based metabolome analysis of serum and saliva from neurodegenerative dementia patients

Tsuruoka, M., Hara, J., Hirayama, A., Sugimoto, M., Soga, T., R. Shankle, R., W., and Tomita, M.

Electrophoresis （Electrophoresis）  34 （ 19 ） 2865-2872 - 2872 2013年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  01730835

　概要を見る

Despite increasing global prevalence, the precise pathogenesis and terms for objective diagnosis of neurodegenerative dementias remain controversial, and comprehensive understanding of the disease remains lacking. Here, we conducted metabolomic analysis of serum and saliva obtained from patients with neurodegenerative dementias (n = 10), including Alzheimer's disease, frontotemporal lobe dementia, and Lewy body disease, as well as from age-matched healthy controls (n = 9). Using CE-TOF-MS, six metabolites in serum (β-alanine, creatinine, hydroxyproline, glutamine, iso-citrate, and cytidine) and two in saliva (arginine and tyrosine) were significantly different between dementias and controls. Using multivariate analysis, serum was confirmed as a more efficient biological fluid for diagnosis compared to saliva; additionally, 45 metabolites in total were identified as candidate markers that could discriminate at least one pair of diagnostic groups from the healthy control group. These metabolites possibly provide an objective method for diagnosing dementia-type by multiphase screening. Moreover, diagnostic-type-dependent differences were observed in several tricarboxylic acid cycle compounds detected in serum, indicating that some pathways in glucose metabolism may be altered in dementia patients. This pilot study revealed novel alterations in metabolomic profiles between various neurodegenerative dementias, which would contribute to etiological investigations. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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Commensal microbe-derived butyrate induces the differentiation of colonic regulatory T cells

Furusawa Y., Obata Y., Fukuda S., Endo T.A., Nakato G., Takahashi D., Nakanishi Y., Uetake C., Kato K., Kato T., Takahashi M., Fukuda N.N., Murakami S., Miyauchi E., Hino S., Atarashi K., Onawa S., Fujimura Y., Lockett T., Clarke J.M., Topping D.L., Tomita M., Hori S., Ohara O., Morita T., Koseki H., Kikuchi J., Honda K., Hase K., Ohno H.

Nature （Nature）  504 （ 7480 ） 446 - 450 2013年

共著,  ISSN  00280836

　概要を見る

Gut commensal microbes shape the mucosal immune system by regulating the differentiation and expansion of several types of T cell. Clostridia, a dominant class of commensal microbe, can induce colonic regulatory T (T reg) cells, which have a central role in the suppression of inflammatory and allergic responses. However, the molecular mechanisms by which commensal microbes induce colonic T reg cells have been unclear. Here we show that a large bowel microbial fermentation product, butyrate, induces the differentiation of colonic T reg cells in mice. A comparative NMR-based metabolome analysis suggests that the luminal concentrations of short-chain fatty acids positively correlates with the number of T reg cells in the colon. Among short-chain fatty acids, butyrate induced the differentiation of T reg cells in vitro and in vivo, and ameliorated the development of colitis induced by adoptive transfer of CD4 + CD45RB hi T cells in Rag1 -/- mice. Treatment of naive T cells under the T reg -cell-polarizing conditions with butyrate enhanced histone H3 acetylation in the promoter and conserved non-coding sequence regions of the Foxp3 locus, suggesting a possible mechanism for how microbial-derived butyrate regulates the differentiation of T reg cells. Our findings provide new insight into the mechanisms by which host-microbe interactions establish immunological homeostasis in the gut. © 2013 Macmillan Publishers Limited. All rights reserved.

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A systems biology approach to suppress TNF-induced proinflammatory gene expressions

Hayashi K, Piras V, Tabata S, Tomita M, Selvarajoo K.

Cell Communication and Signaling （Cell Communication and Signaling）  11 （ 1 ） 84 2013年

共著

　概要を見る

Background: Tumor necrosis factor (TNF) is a widely studied cytokine (ligand) that induces proinflammatory signaling and regulates myriad cellular processes. In major illnesses, such as rheumatoid arthritis and certain cancers, the expression of TNF is elevated. Despite much progress in the field, the targeted regulation of TNF response for therapeutic benefits remains suboptimal. Here, to effectively regulate the proinflammatory response induced by TNF, a systems biology approach was adopted. Results: We developed a computational model to investigate the temporal activations of MAP kinase (p38), nuclear factor (NF)-κ;B, and the kinetics of 3 groups of genes, defined by early, intermediate and late phases, in murine embryonic fibroblast (MEF) and 3T3 cells. To identify a crucial target that suppresses, and not abolishes, proinflammatory genes, the model was tested in several in silico knock out (KO) conditions. Among the candidate molecules tested, in silico RIP1 KO effectively regulated all groups of proinflammatory genes (early, middle and late). To validate this result, we experimentally inhibited TNF signaling in MEF and 3T3 cells with RIP1 inhibitor, Necrostatin-1 (Nec-1), and investigated 10 genes (Il6, Nfkbia, Jun, Tnfaip3, Ccl7, Vcam1, Cxcl10, Mmp3, Mmp13, Enpp2) belonging to the 3 major groups of upregulated genes. As predicted by the model, all measured genes were significantly impaired. Conclusions: Our results demonstrate that Nec-1 modulates TNF-induced proinflammatory response, and may potentially be used as a therapeutic target for inflammatory diseases such as rheumatoid arthritis and osteoarthritis. © 2013 Hayashi et al.; licensee BioMed Central Ltd.

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Metabolomic profiling of the response of susceptible and resistant soybean strains to foxglove aphid, Aulacorthum solani Kaltenbach

Sato D., Akashi H., Sugimoto M., Tomita M., Soga T.

Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences （Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences）  925   95 - 103 2013年

共著, 査読有り,  ISSN  15700232

　概要を見る

Aphid infection reduces soybean (Glycine max [L.] Merr.) yield. Consequently, cultivation of aphid-resistant strains is a promising approach to pest control, and understanding the resistance mechanism is of importance. Here, we characterized the resistance of soybeans to foxglove aphid, Aulacorthum solani Kaltenbach, at the metabolite level. First, we evaluated aphid mortality and settlement rates on the leaves of two soybean strains, 'Tohoku149' and 'Suzuyutaka', and found that the former had strong resistance soon after introduction of the aphids. The metabolomic response to aphid introduction was analyzed using capillary electrophoresis-time-of-flight mass spectrometry. We found the following three features in the profiles: (1) concentrations of citrate, amino acids, and their intermediates were intrinsically higher for Tohoku149 than Suzuyutaka, (2) concentrations of several metabolites producing secondary metabolites, such as flavonoids and alkaloids, drastically changed 6. h after aphid introduction, and (3) concentrations of TCA cycle metabolites increased in Tohoku149 48. h after aphid introduction. We also profiled free amino acids in aphids reared on both soybean strains and under starvation, and found that the profile of the aphids on Tohoku149 was similar to that of the starved aphids, but different to that of aphids on Suzuyutaka. These tests confirmed that aphids suck phloem sap even from Tohoku149. This study demonstrates the metabolomic profiles of both soybean strains and aphids, which will contribute to the molecular level understanding of mechanisms of soybean resistance to aphids. © 2013 Elsevier B.V.

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Merging multiple omics datasets in silico: Statistical analyses and data interpretation

Arakawa K., Tomita M.

Methods in Molecular Biology （Methods in Molecular Biology）  985   459 - 470 2013年

共著, 査読有り,  ISSN  10643745

　概要を見る

By the combinations of high-throughput analytical technologies in the fields of transcriptomics, proteomics, and metabolomics, we are now able to gain comprehensive and quantitative snapshots of the intracellular processes. Dynamic intracellular activities and their regulations can be elucidated by systematic observation of these multi-omics data. On the other hand, careful statistical analysis is necessary for such integration, since each of the omics layers as well as the specific analytical methodologies harbor different levels of noise and variations. Moreover, interpretation of such multitude of data requires an intuitive pathway context. Here we describe such statistical methods for the integration and comparison of multiomics data, as well as the computational methods for pathway reconstruction, ID conversion, mapping, and visualization that play key roles for the efficient study of multi-omics information. © Springer Science+Business Media, LLC 2013.

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Role of Na⁺-Ca²⁺ exchange in neonatal and adult ventricular cells: A simulation study

Sano H., Naito Y., Tomita M.

Computing in Cardiology 39   877 - 880 2012年12月

ISSN  2325887X

　概要を見る

The Na+-Ca2+ exchange assumes considerable importance in neonatal cells with a morphologically sparse sarcoplasmic reticulum. Our simulation shows that the neonatal ventricular cell consumed larger amount of ATP than the adult ventricular cell, owing to a long relaxation time. The amount of ATP consumed per beat was reduced to the amount equivalent to the adult ventricular cells, thus increasing the relative current density of Na +-Ca2+ exchange by 4-fold, which is consistent with the observed current density in the neonatal rabbit ventricular cells. © 2012 CCAL.

Prediction of potentially unstable electrical activity during embryonic development of rodent ventricular myocytes

Okubo C., Sano H., Naito Y., Tomita M.

Computing in Cardiology 39   301 - 304 2012年12月

ISSN  2325887X

　概要を見る

In order to evaluate developmental changes in embryonic ventricular cells at early embryonic (EE) and late embryonic (LE) stage, we aimed to predict potentially unstable action potentials (APs) that could be lethal to developing ventricular cells. Two models of the Kyoto and the Luo-Rudy model were used for simulation of 512 representative combinations by switching the relative activities of 9 ionic components whose activities vary between the EE and LE stages. Out of these 512 combinations in Kyoto model, 144 combinations were predicted potentially unstable resulting from combinations of funny current (If), inward rectifier current (IK1), sustained inward current (Ist), L-type Ca2+ current (ICaL), and Na+ current (INa). Other 208 and 160 combinations were predicted quiescent membrane potentials and regular spontaneous APs. Based on these results, we suggest that sequential switches of the relative activities of INa, If, and IK1 enable cells to avoid unstable patterns. © 2012 CCAL.

Clarification as to why alcoholic beverages have the ability to induce superconductivity in Fe <inf>1+d</inf>Te <inf>1-x</inf>S <inf>x</inf>

Deguchi K., Sato D., Sugimoto M., Hara H., Kawasaki Y., Demura S., Watanabe T., Denholme S., Okazaki H., Ozaki T., Yamaguchi T., Takeya H., Soga T., Tomita M., Takano Y.

Superconductor Science and Technology 25 （ 8 ）  2012年08月

ISSN  09532048

　概要を見る

To elucidate the mechanism as to why alcoholic beverages can induce superconductivity in Fe 1+dTe 1xS x samples, we performed component analysis and found that a weak acid such as an organic acid has the ability to induce superconductivity. Inductively coupled plasma spectroscopy was performed on weak acid solutions post-annealing. We found that the mechanism of inducement of superconductivity in Fe 1+dTe 1xS x is the deintercalation of excess Fe from the interlayer sites. © 2012 IOP Publishing Ltd.

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The rice proteogenomics database OryzaPG-DB: Development, expansion, and new features

Helmy M., Sugiyama N., Tomita M., Ishihama Y.

Frontiers in Plant Science （Frontiers in Plant Science）  3 （ APR ） 65 2012年04月

　概要を見る

Our recently developed rice proteogenomics database (OryzaPG-DB) is the first sustainable resource for rice shotgun-based proteogenomics, providing information on peptides identified in rice protein digested peptides measured by means of liquid chromatography-tandem mass spectrometry (LC-MS/MS), and mapping of the peptides to their genomic origins and the genomic novelty of each peptide. The sequences of the peptides, proteins, cDNAs and genes, and the gene annotations are available for download in FASTA and GFF3 formats, respectively. Further, an annotated visualization of the gene models, corresponding peptides, and genomic novelty is available for each gene, and MS/MS spectra are available for each peptide. In this article, we discuss the utilization of OryzaPG-DB and report on its development, recent content expansions, and newly added features in the current version (OryzaPG-DB v1.1). © 2012 Helmy, Sugiyama, Tomita and Ishihama.

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Changes in the charged metabolite and sugar profiles of pasteurized and unpasteurized Japanese sake with storage

Sugimoto M., Kaneko M., Onuma H., Sakaguchi Y., Mori M., Abe S., Soga T., Tomita M.

Journal of Agricultural and Food Chemistry （Journal of Agricultural and Food Chemistry）  60 （ 10 ） 2586 - 2593 2012年03月

ISSN  00218561

　概要を見る

Japanese sake (rice wine) is commonly heat treated (pasteurized) to maintain its quality. In this study, temporal changes in the metabolite profiles of pasteurized and unpasteurized sake were investigated during storage. Metabolomic analyses were conducted for eight sets of pasteurized and unpasteurized sake obtained from single process batches stored at 8 or 20 °C for 0, 1, 2, or 4 months. Capillary electrophoresis time-of-flight mass spectrometry and liquid chromatography tandem mass spectrometry were used to obtain charged metabolite and sugar profiles, respectively. The total amino acid concentration decreased with storage, and the decrease was faster in pasteurized sake than in unpasteurized. The organic acid concentrations were relatively constant in both types of sake. Peptide and glucose concentrations increased and polysaccharide concentrations decreased in unpasteurized sake, while they were relatively constant in pasteurized sake. Rather than stabilizing the sake metabolite profile during storage, pasteurization results in characteristic changes compared to unpasteurized sake. © 2012 American Chemical Society.

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